Identification of eccentricity related-faults characteristic frequencies in induction motors using a programmable power source

With the aim of developing an expert system for condition monitoring of cage rotor induction motors fed by power inverters, laboratory tests have been performed on a motor with artificially created eccentricity in order to identify as many fault signatures as possible. The technique used to detect faults is Motor Current Signature Analysis and in this paper it is analyzed if the spectra around the time harmonics 5, roduced by an inverter are suitable for condition monitoring. monitoring. But, taking into account that the harmonic content of the voltage waveform and the amplitude of the harmonics depend on the voltage supply, in order to establish diagnosis criteria independent of the voltage supply, a programmable power source has been used as a motor supply. The results are discussed and some guidelines for condition monitoring are suggested.